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Eight mixed-valence pentanuclear CuI4CuII clusters constructed by 1,2,3-triazole or tetrazole and different mono-phosphine ligands have been fabricated. They exhibit excellent photothermal conversion performance.

For investigating the regulatory effects of the 1,3,5-trithiane (3S) in the formation of silver-alkynyl clusters, two new tetra-nucleus silver-alkynyl clusters, namely, [(3S)4Ag4(PhC≡C)(OTf)2]·OTf·CH3OH (1, OTf = CF3SO3−), and [(3S)2Ag4(tBuC≡C)(tfa)3]n (2, tfa = CF3CO2−), were synthesized and their unique structures were investigated by single-crystal X-ray diffraction, Fourier-transform infrared spectroscopy, and powder X-ray diffraction analysis. Cluster 1 was a discrete cationic tetra-nucleus cluster co-ligated by 3S and phenylacetylene. Cluster 2 was a 2D coordination polymer based on a structurally similar tetra-nucleus cluster linking by 3S. Both clusters show excellent thermal stability and bright solid-state photoluminescence properties at room temperature. This work opens the door to using the supramolecular ligand-thiocrown ether to synthesize Ag clusters of attractive properties.

As redox-active based supercapacitors are known as highly desirable next-generation supercapacitor electrodes, the targeted design of two ferrocene-functionalized (Fc(COOH)2 ) clusters based on coinage metals, [(PPh3 )2 AgO2 CFcCO2 Ag(PPh3 )2 ]2 ⋅7 CH3 OH (SC1 : super capacitor) and [(PPh3 )3 CuO2 CFcCO2 Cu(PPh3 )3 ]⋅3 CH3 OH (SC2 ), is reported. Both structures are fully characterized by various techniques. The structures are utilized as energy storage electrode materials, giving 130 F g-1 and 210 F g-1 specific capacitance at 1.5 A g-1 in Na2 SO4 electrolyte, respectively. The obtained results show that the presence of CuI instead of AgI improves the supercapacitive performance of the cluster. Further, to improve the conductivity, the PSC2 ([(PPh3 )2 CuO2 CFcCO2 ]∞ ), a polymeric structure of SC2 , was synthesized and used as an energy storage electrode. PSC2 displays high conductivity and gives 455 F g-1 capacitance at 3 A g-1 . The PSC2 as a supercapacitor electrode presents a high power density (2416 W kg-1 ), high energy density (161 Wh kg-1 ), and long cycle life over 4000 cycles (93 %). These results could lead to the amplification of high-performance supercapacitors in new areas to develop real applications and stimulate the use of the targeted design of coordination polymers without hybridization or compositions with additive materials.

Advancement of the synthesis and control of the self-assembly process of new high-nucleus silver clusters with desired structures is important for both the material sciences and the many applications. Herein, three new silver clusters, 20-, 22-, and 8-nucleus, based on alkynyl ligands were constructed and their structures were confirmed by single-crystal X-ray diffraction, powder X-ray diffraction, elemental analyses, and Fourier-transform infrared spectroscopy (FT-IR). For the first time, the trivalent tetrahedron anion of AsO

A one dimensional high-nucleus silver polymer (SSc: silver supercapacitor) was designed by a simple and single-step synthesis. This stable highly conductive metallic polymer without any modification steps such as pyrolysis or doping provides a desirable path for electron transfer and shows high capacitance as a non-hybrid electrode (specific capacitance of 827 F g−1 at 5 A g−1). This polymer could tolerate low to high scan rates (200 mV s−1 to 1 V s−1) and exhibit rectangular cyclic voltammetry shapes, high power density and long cycle life over 5000 cycles (90.7%). These results could promise the development of new types of high-performance supercapacitors by overcoming the low conductivity and the limited capacity challenges of known structures without the need for any modification which is unique in non-hybrid electrode materials.

Extensive composition engineering research has been conducted on bandgap tunability, but the combination of two mechanisms for better photon harvesting over a wide range has rarely happened; this is of great importance for improving photocatalytic efficiency with sunlight. In order to enable concurrent heterogenic Fenton and Fenton-like reactions for dye degradation, two novel ferrocene-functionalized clusters, [(PPh3)3CuO2CFcCO2Cu(PPh3)3]·3CH3OH (D1) and [(PPh3)2AgO2CFcCO2Ag(PPh3)2]2·7CH3OH (D2) were designed, synthesized and characterized by multiple techniques. These chemically and thermally stable coinage clusters exhibit high photocatalytic activity towards the degradation of methylene blue as a model dye in the presence of H2O2 under direct sunlight irradiation. The degradation performance of complex D1 is about twice that of complex D2. The catalytic performance of D1 (15 000 mg g−1 in less than 20 min) is superior to those of other reported complexes, which can be attributed to the high level of generated hydroxyl radicals which are the most active species for dye degradation in the combination of Fenton and Fenton-like mechanisms. In addition to the degradation carried out with the aid of the Fe(III) of ferrocene, based on the Fenton mechanism, the photogenerated holes trapped by Cu(I) act as catalysts in the Fenton-like mechanism to produce an excess of hydroxyl radicals, adding to those formed via scavenging of photogenerated electrons by hydrogen peroxide. Furthermore, the performance of D1 in the presence of H2O2 as a dual photocatalyst under natural sunlight irradiation needs no pH adjustment which is a unique characteristic. This bilateral compound offers a promising strategy for the design of new photocatalysts.

For further understanding of the molecular absorption mechanisms of photothermal conversion by coordination compounds, two newly prepared xanthene-functionalized silver(I) complexes, [Ag2(X9A)2(dppm)2] (1) (where dppm = bis(diphenylphosphino)methane and X9A = 9H-xanthene-9-carboxylato(-1)) and [Ag4(X9A)4(dppm)2]·6CH3OH (2), have been isolated and structurally characterized. We report here the syntheses, crystal structures, characterizations by various spectroscopic (IR, UV–Vis, powder XRD) techniques, as well as photothermal conversion performance of 1 and 2. Their X-ray crystal structures reveal that 1 is a binuclear silver(I) coordination compound bridged by two dppm molecules with two monodentate 9H-xanthene-9-carboxylato(-1) ligands, and 2 can be described as the dimer of 1 bridged by two 9H-xanthene-9-carboxylato(-1) anions in the μ3-η1,η2 coordination mode. Their photothermal conversion experimental results give new insight into understanding the molecular mechanisms for improving the performance of photothermal conversion molecular materials.

The first silver nanocluster with an octahedral template of TeO66– was synthesized as a neutral 36-nucleus nanocluster, and its structure was demonstrated using single-crystal X-ray diffraction, Fo...

In order to study the charge effect on the formation of an anion-templated silver cluster, a trivalent tetrahedral anion was incorporated into the silver assembly. A 26-nuclear silver cluster was prepared, and its structure was confirmed by single-crystal X-ray diffraction. Also, the resulting structure was characterized by powder X-ray diffraction data. Its light absorption and photoluminescent properties were studied by solid-state UV diffuse-reflectance and fluorescence spectroscopy. Compared with the other reported silver clusters with tetrahedral anion templates, the more negative VO43- anion led to the formation of a bigger silver cluster. Also, the supramolecular motif O-H(CH3OH)···O(trifluoroacetate) was confirmed on the cluster surface for the first time.

Gas hydrates hold great potential in the field of energy storage & transportation. However, the stochastic induction time and low formation rate restricted the large-scale industrialization of gas hydrate technology, which need to be improved through effective methods. Superabsorbent hydrogels (SAHs) are lightly cross-linked polymers with three-dimensional networks that can absorb and retain a large amount of water or aqueous solution. Due to the strong absorption and retention capabilities, SAHs have been added in the system to facilitate gas hydrate formation via increasing mass transfer and improving promoter recyclability. However, the interactions among gas, water and hydrogels are complicated, and the usages are diverse, and the promotion mechanisms were underexplored. This paper reviews the existing cases applying SAHs in gas hydrate formation, and analyzes the influencing mechanisms of SAHs; and meanwhile proposes a concept of SAH-based solid-state water (SSW) system, and evaluates its application potential in promoting gas hydrate formation, and further prospects its modification and integration possibilities for being a hydrate promoter.

For achieving solar absorber and conversion molecular materials with excellent photothermal conversion ability, five mononuclear Copper(II) coordination compounds have been designed and isolated. They are fully characterized by IR, Powder XRD, Solid-state UV, and TGA. Single-crystal X-ray structural analysis reveals that they are typical photothermal conversion molecules with double chromophores: one antenna chromophore (NT group here) and the second chromophores (Cu(dmap)42+, Cu(dmap)22+, Cu(bpy)22+ and Cu(phen)22+). Both chromophores have great influence on their solid-state optical absorption. Their photothermal conversion experiments show that compounds 3, 4 and 5 have the better results (the highest temperature increment 21.7 ℃ and equilibrium temperature ~ 60.7 ℃) than compounds 1 and 2. Those results give some clues for illustrating the molecular mechanisms of solar absorber and photothermal conversion molecular materials.

Two new silver clusters, [Ag6(PhC C)2(bpy)4(NO3)4] (1), bpy = 2,2′-bipyridine, Ag8(Phen)4(NEA)8(CH3CN)2 (2), NEA = naphthalene acetic acid, were synthesized with assistance of ultrasonic irradiation and their unique structure investigated by single-crystal X-ray diffraction, Fourier-transform infrared spectroscopy (FT-IR), powder X-ray diffraction analysis (PXRD) and Ultraviolet–visible spectrum (UV–Vis). Thermal stability of the clusters were studied through thermogravimetric analysis (TGA). The photoluminescence analysis of 2 was also carried out. Clusters 1 and 2 show the absorption bands at λmax in the range 200–380 nm and 310 nm, respectively. The band gap widths for clusters are 3.05 eV and 3.20 eV. The Ag…Ag contact range in the cluster 1 is 2.7211(4) A–3.1102(3) A and for the cluster 2 is 2.867–3.047 A.

In order to achieve a light-harvesting system with excellent photo-thermal conversion property, three naphthyl(NT)-functionalized Copper(II) coordination compounds have been designed and isolated. They are characterized by IR, Powder XRD, UV, and TGA. Single-crystal X-ray structural analysis reveals that {[Cu4(bpy)4(1-NTAA)5](BF4)3∙3(CH3OH)∙H2O}∞ (1) has 1D chain structure, {[Cu2(1-NTAA)4(CH3CN)2]∙2(CH3CN)} (2) and {[Cu2(2-NTA)4(CH3CN)2]∙2.5(CH3CN)} (3) have similar paddle-wheel structures. Utilizing the introduction of NT-groups into copper(II) centers, all three compounds exhibit good solid-state optical absorption in a nearly full solar spectral region. The coordination polymer 1 exhibits the quickest temperature rising (nearly 2 ℃/min from the very beginning), the highest temperature increment (12 ℃) and equilibrium temperature (40 ℃) over the other two compounds in the photothermal conversion experiments. Those results point out the direction of molecular design for enhancing photothermal conversion performance.

In order to develop an easy and rapid identification method for distinguishing CH3OH from C2H5OH, a new carbonate-based trinuclear Cu(II) precursor, [Cu3(bpy)6(μ3-CO3)(CH3OH)](BF4)4·(CH3OH)2·(H2O)2 (1), has been isolated. We report here the synthesis, crystal structure, and characterizations by various spectroscopic (IR, UV–Vis, powder XRD) techniques, as well as the solvatochromic behavior of this coordination compound. Its X-ray crystal structure reveals that the main structure of 1 consists of three [(bpy)2Cu]2+ centers, which are bridged by carbonate via a μ3-η1,η1,η1 fashion. Strong O–H⋯O hydrogen bonding between the carbonate and solvent molecules has been observed for the first time in similar structures. Its ground powder exhibits solvatochromic behavior that selectively distinguishes CH3OH from C2H5OH.

Interlayer is a kind of rock body that reflects the seepage barrier in the reservoir sandstones. As the interlayer playing a blocking role of hydrocarbon accumulation, we can better understand the characteristics of the reservoir heterogeneity through the analysis of the causes and spatial distribution of the interlayer. Empirically, identification of four types of interlayer, including muddy interlayer, calcium interlayer, physical layer, and indistinguishable interlayer, contributes to effective production of tight gas sandstones. Each category of interlayer has a separate characteristic of the lithology and logging curves. Identifying interlayer provides a way to analyzing spatial distribution of interlayer in the tight gas field. 2-D and 3-D geological models corresponding to the distribution of interlayer can be able to establish to characterize distribution variations within the reservoirs, which show the space matching relation serving for the tight gas production.

The prevalence of Android makes it face the severe security threats from malicious apps. Many Android malware can steal users’ sensitive data and leak them out. The data flow analysis is a popular technique used to detect privacy leakages by tracking the sensitive information flow statically. In practice, an effective data flow analysis should employ inter-procedure information tracking. However, the Android event-driven programming model brings a challenge to construct the call graph (CG) for a target app. This paper presents a method which employs the inter-procedural and context-sensitive data flow analysis to detect privacy leakage in Android apps. To make the analysis accurate, a flow-sensitive and points-to call target analysis is employed to construct and improve the call graph. A prototype system, called PDroid, has been implemented and applied to some real malware. The experiment shows that our method can effective detect the privacy leakages cross multiple method call instances.

To solve the problem of too many variable numbers which makes the model complex, a kind of auxiliary variables selection method is established. After that, soft sensing of lead-acid battery capacity is put forward. First, the RReliefF method is adopted to define quantitatively the influence of auxiliary variables. Then, the soft sensing model is built up with all the combination of auxiliary variables with BP neural network. Simulation results show that the soft sensing of battery capacity is established ideal. It provides theoretical feasibility to omit the battery discharge capacity in the process of production inspection process.

Sequence stratigraphic features of the Jurassic succession in Central Junggar Basin were investigated by integrating multiple materials including cores, well and seismic data. Due to their unique formation mechanism, sequences of the target interval were analyzed with a binary systems tract mode (each complete sequence contains a transgressive systems tract and a highstand systems tract) rather than the traditional one. Basic principles and analytical methods of high-resolution sequence stratigraphy were also applied to this research. By adopting cyclic correlation and hierarchical control techniques, eight sequences (Sq1-Sq8) were identified in the target interval. Especially, coal seams are of great significance in the sequence identification and they were considered to be closely relevant to maximum flooding surfaces (mfs).

With the method of the high resolution sequence stratigraphy and sedimentology theory, oil-bearing sand bodies have been accurately recognized and descripted which could provide precisely geological data for 3-D modeling and numerical simulation. It has the vital significance for the development of oilfield during the late stage of high water cut. According to the drilling, logging, seismic and analytical experiments data, the results show that the study area can be divided into one long-term base level cycle, four middle-term base level cycles, sixteen short-term base level cycles and twenty-eight super short-term base level cycles. Based on the classification of base-level cycles, control functions of cycles which have effects on the sediment environment have been discussed. And with the application of the chronostratigraphic correlation fine stratigraphic correlation, 10 high resolution sequence stratigraphic frameworks are established in the direction that is parallel and perpendicular to the source.

This paper describes the identification of waterflooded zones and the impact of waterflooding on reservoir properties of sandstones of the Funing Formation at the Gao 6 Fault-block of the Gaoji Oilfield, in the Subei Basin, east China. This work presents a new approach based on a back-propagation neural network using well log data to train the network, and then generating a cross-plot plate to identify waterflooded zones. A neural network was designed and trained, and the results show that the new method is better than traditional methods. For a comparative study, two representative wells at the Gao 6 Fault-block were chosen for analysis: one from a waterflooded zone, and the other from a zone without waterflooding. Results from this analysis were used to develop a better understanding of the impact of waterflooding on reservoir properties. A range of changes are shown to have taken place in the waterflooded zone, including changes in microscopic pore structure, fluids, and minerals.

Gene editing is a kind of technologies that makes precise modification to the genome. It can be used to knock out/in and replace the specific DNA fragment, and make accurate gene editing on the genome level. The essence of the technique is the DNA sequence change with use of non homologous end link repair and homologous recombination repair, combined with specific DNA target recognition and endonuclease.This technology has wide range of development prospects and high application value in terms of scientific research, agriculture, medical treatment and other fields. In the field of gene therapy, gene editing technology has achieved cross-time success in cancers such as leukemia, genetic disorders such as hemophilia, thalassemia, multiple muscle nutritional disorders and retrovirus associated infectious diseases such as AIDS and other diseases. The preparation work for new experimental methods and animal models combined with gene editing technology is under rapid development and improvement. Laboratories around the world have also applied gene editing technique in prevention of malaria, organ transplantation, biological pharmaceuticals, agricultural breeding improvement, resurrection of extinct species, and other research areas. This paper summarizes the application and development status of gene editing technique in the above fields, and also preliminarily explores the potential application prospect of the technology in the field of traditional Chinese medicine, and discusses the present controversy and thoughts.

Background: Astrocytomas and oligodendrogliomas are two types of primary Central nervous system (CNS) tumors. Because of the cytoarchitectural variability and lacking of accurate differential diagnosis biomarkers, distinguishing between these neoplasms remains a challenge. Method: In this study, we utilized the tumor tissue proteome to distinguish the astrocytomas and oligodendrogliomas. The protein samples from astrocytomas and oligodendrogliomas tumor tissues were analyzed by 2DLC/MS/MS and isobaric tags for relative and absolute quantitation (iTRAQ) quantification. The differential proteins were analyzed by IPA software, and three identified differential proteins were validated by Western Blot. Results: A total of 2189 proteins were identified, including 150 upregulated and 103 downregulated in astrogliomas compared to oligodendrogliomas. By bioinformatics analysis, compared to oligodendrogliomas, the astrocytomas is more likely tend to cell proliferation, migration and the tumor angiogenesis, indicating astrocytomas was more malignant than the oligodendrogliomas. Pathway analysis showed that members of Rho Family GTPases were remarkably changed between astrocytomas and oligodendrogliomas. Two member of Rho family of GTPases, Cell division control protein 42 homolog (CDC42) and Transforming protein RhoA (RHOA) were over-expressed in astrocytomas and oligodendrogliomas, respectively. Discussion: Above data indicated that the differential proteome could be useful to distinguish between astrocytomas and oligodendrogliomas, especially the Rho family of GTPases. Differential proteome could partially reflect the pathological characteristics of these two diseases.